POS1155 THE INTERNATIONAL X-LINKED HYPOPHOSPHATAEMIA (XLH) REGISTRY: OVERVIEW OF THE DATA SET
Authors: G. Ariceta, J. Liu, A. Williams, S. Wood, D. Schnabel
Journal: Annals of the Rheumatic Diseases (2022)

Background X-Linked Hypophosphataemia (XLH) is a rare, progressive, lifelong, hereditary renal tubule phosphate-wasting disorder characterised by a pathological increase in fibroblast growth factor 23 concentration/activity. 1 Despite XLH being increasingly recognised as a chronic progressive disease, there are few data documenting its natural history or the impact of treatment on patient outcomes. 2 The International XLH Registry was established to address this lack of information on XLH to help inform future clinical management. The Registry will collect data to characterise the treatment, burden of disease, disease progression and long-term outcomes of XLH. Objectives To provide an overview and status update of the International XLH Registry as of 31 December 2021. Methods The International XLH Registry ( NCT03193476 ) was initiated in August 2017, aims to recruit 1,200 children and adults with XLH, and will run for 10 years. This Registry is an international, multicentre, non-interventional data collection programme and will provide the largest single dataset representing children and adults with XLH. To be eligible for inclusion in the registry, patients must meet all the following criteria:1) Male or female subjects of all ages; 2) Diagnosis of XLH with clinical, radiological, biochemical and/or genetic findings consistent with XLH. The Registry captures any treatment details and clinical outcome variables in patients with XLH and patients are followed for as long as informed consent (and assent, where applicable) and regulatory permissions are maintained. Only data collected during standard routine examinations are recorded within the Registry, and no specific examinations/data entries are mandated. Parameters collected at baseline included demographics, medical and treatment history, and clinical presentation data. The conduct of the International XLH Registry is overseen by 17 Steering Committee physician members representing the region. Results As of 31 December 2021, 1,043 subjects diagnosed with XLH were enrolled from 88 hospital sites in 19 countries. The geographic distribution of subjects is as follows: Belgium n=29, Bulgaria n=7, Czech Republic n=8, Denmark n=23, France n=267, Germany n=79, Hungary n=11, Ireland n=5, Israel n=21, Italy n=88, The Netherlands n=26, Norway n=23, Portugal n=9, Slovakia n=5, Slovenia n=3, Spain n=55, Sweden n=43, Switzerland n=17, and the UK n=324. A further 30 sites are yet to enrol (including sites in Austria and Latvia). Overall, 400 adults (18–29y, n=116; 30–39y, n=81; 40–49y, n=95; 50–59y, n=58; ≥60y, n=50) and 620 paediatric subjects (&lt;5y, n=138; 5–12y, n=321; 13–17y, n=161) have been enrolled (date of birth not reported, n=23). The majority of enrolled subjects are female (648 (62.1%), with 372 male (35.7%) and 23 for whom sex was not reported (2.2%). The quantity of data from the patients included in this Registry will enable ongoing snapshot and prospective analyses to be conducted over the coming years to answer research questions and inform clinical practice. Conclusion This International XLH Registry forms the largest dataset of subjects with XLH collected to date. Patients have been recruited from a wide geographical region and baseline demographics are consistent with a hereditary X-linked dominant disease. Information collected during the 10-year Registry duration will generate real-world evidence to help inform clinical practice throughout the region, with the aim of improving the care and quality of life of adults and children living with this debilitating disease. References [1]Haffner D, et al . Nat Rev Nephrol 2019;15(7):435–455. [2]Padidela R, et al . Orphanet J Rare Dis. 2020; 15:172. Acknowledgements Authors acknowledge the contribution of all International XLH Registry Steering Committee members, and all the investigators participating in the International XLH Registry. Disclosure of Interests Gema Ariceta Speakers bureau: I have received honoraria for lectures, presentations, or educational events from Alexion Pharmaceuticals, Recordati Rare Disease, Advicenne, Chiesi, Kyowa Kirin, Consultant of: I have participated on Advisory Boards for Alexion Pharmaceuticals, Advicenne, Chiesi, Dicerna, and Alnylam., Jonathan Liu Employee of: Employee of Kyowa Kirin International, Angela Williams Employee of: Employee of Kyowa Kirin International, Sue Wood Employee of: Employee of Kyowa Kirin International, Dirk Schnabel Speakers bureau: I received an honorarium from various companies for scientific lectures (i.e. Ascendis, BioMarin, Ferring Pharma, Hexal / Sandoz, Ipsen Pharma, Kyowa Kirin, Merck Serono, Novo Nordisk), Consultant of: BioMarin, Kyowa Kirin